Logic Masters Deutschland e.V.

SudokuPad link (via tinyURL)

--Draw some regions and fill in digits from 1-9 such that no digit repeats in a row, column, or region. It is up to the solver to determine the number of regions and the digits they contain;
--White diamonds indicate that two cells are in the same region;
--Black diamonds indicate that two cells are in different regions. The difference between cells separated by a black diamond is the same as the difference between the size of their respective regions (the size of a region is the number of cells in that region);
--The digit in each circle is the size of the region that contains it;
--No two regions can have the same size.